I have been following several topics the last while and have decided that there is so much mis-information about this engine that I thought I would put together some documents to help with both maintenance and flight peoples - and those armchair pundits that post total rubbish regarding the engine operation.

My friends told me I should sell this info - but I know how that works - In Canada I make 1 sale - and from then on it gets "Shared". In the US - it just gets hacked. Overseas - it gets a little politer hacking - is "Politer" actually a word??

So in the spirit of things I have decided the quickest way to get this stuff out would be to use the Creative Commons approach - if you don't know what that is then Google is your friend.

The link below is to my website and will open showing 3 documents - they are all free for the downloading. They are all PDF documents so all you need is the Acrobat Reader to access them.

They are all based on the small / medium engine series of the PT6 - so up to about the 40 series.

One is on the operation of the Bendix FCU - I have literally built the FCU on paper.

Another one is on rigging the engine.

The third one is a descriptive set of notes on how the engine control system operates.

These might help with understanding and maintaining the engine

- but remember

These are Not OFFICIAL PUBLICATIONS and are FOR TRAINING PURPOSES ONLY

Download them - share them - give them away to your favorite friends - I have relinquished all control of the documents so you can use them in your own training department - or self study - or just to make your computer look smart when someone drops by to see what you are doing.

I had a lot of fun developing these - and after 40 years in the aviation maintenance and maintenance training business I thought it was time to give something back. It's a bit late for Christmas - but here is a present from me to you.

A link to your 3 documents was posted on another forum. It looked interesting so I down loaded them and started flipping through the docs. On page 3 of the Pratt & Whitney PT6A – Small Engine Control System doc is a picture of a King Air panel that I thought looked familiar. It is in fact a photo of my panel from my C90 King Air from a few years ago. I have posted it several times on the web and am glad to see that it is being used for a worthy purpose

Thanks for the info - I thought I had taken out any photos that I had not shot myself - but it looks like I missed this one??

I was working with another person when I started this project a few years ago and this was one of the photos that they contributed - and I assumed they had taken the photo as they had access to a large number of Beech Aircraft Types.

I appreciate the heads up and if you are OK with it in the document then I am grateful for its' use.

I can modify the source file with a credit to the photo and reload it to the site if that is what you would like - or you can be like me and just offer it as a gift. The option is yours.

@ avionimc - I have heard a lot of diffent things about the design origin of the PT6 but a logging camp stove has never crossed my path!!!

The "PT" part stands for Propeller Turbine. The engine is also made as a "ST" engine - which is a Shaft Turbine. Used in helicopters - trains - snowblowers - trucks - boats - pumps - and cars. The "TwinPac" in the Bell 212 was unique in it's day as the combining gearbox - normally made by the airframe manufacturer -was made by the engine manufacturer.

As a side note - my understanding for the reverse flow design was that P&W wanted to be able to retrofit the existing piston engine fleet by having the ability to produce a firewall forward installation that was completely independent. Thus the forward exhaust system requires no modifications to the airframe like the transition tubes etc for rear exhaust engines.

One of the dumbest designs was the placement of the landing lights on the Twin Otter - Yup right behind the stacks!!

FYI - a "spool consists of a turbine and a compressor. Turbofan engines often consider the Fan section a spool as the inboard blades are considered to be the first stage compressor. For some reason they don't consider a propeller in the same light.

Thanks MX Trainer. There is very little technical information about the PW100on the internet(hint hint).

I am curious what PWC did to make the PT6-28 engine different from the -27for the high altitude capability.

Hope I am not asking too many questions. It is just that I flew the DHC-6 with the -27 and the King Air with the -28(I think out BE-99 had it as well) and always wondered what the real difference was internally.

AFAIK - the -28 had an uprated compressor with more airflow - an uprated hot section - and was operated with more torque than the -27. Also I seem to remember that the compressor bleed valves were also different. Part of the upgrade was for higher altitude performance but also for increased airflow for bleed air used for heating and pressurization purposes. I don't have access to anyone at Pratt that is in the know any more so this is the best I can do. Hopefully it is enough or someone who has more experience with the engine than I do can explain further.

As for the P&W 100 series engine - I have a pile of stuff for it - from Dash 8 - EMB Brazzie - D328 etc. but the problem is that it is still a production engine and probably more important all the training materials I have developed were for specific companies and as such are subject to copy-write issues. Thus it is not easy to just dump them onto the internet - even for free!! Some companies like "Flight Safety" are fully aware of how much of their stuff gets ripped off and until you have actually had to sit in front of a computer for years producing manuals and training material you have no idea as to how much work - and money - it takes to do this. Now if someone wants to hire me to do a set of free manuals I come pretty reasonable but I think you would be very surprised at the end cost.

A small aircraft course - say something like the Beech 1900D - will cost in the neighborhood of about $35,000.00 Cdn. to have produced by someone like me. If I was to see that material offered for sale on the internet or even given away for free; as the owner of the material I would be a little more than upset.

On that note - if I can find a set of very old training documents in my archive I might be able to make a P&W 100 manual into a digital file without a lot of work. But it is going to depend on where the source material came from. If I can use it without copy-right infringement then I will put it up for everyone.

Are the 4 documents that you posted last fall still available? The link does not seem to work. They have become popular on BeechTalk Turbine Forum. I have been passing them along to others. Hope that is OK. If so, a new link to them would be of great use. Thanks for your hard work.

I have done 10 aircraft ground schools over thirty years from Fokker F27 to B777, covering the RR Dart, JT8D, RB211 and CFM56. Your PT6A is by far the most lucid explanation of a fuel system I have seen.

I am curious what kind of software can be used to make detailed drawings of the FCU system like the ones P&WC puts out in their training manuals. Does anyone know what software could be used to make such drawings and also maybe animate them to explain how the system works? AutoCad? Other programs? What would be the best?